3.8
SEL-351A Relay
Instruction Manual
Date Code 20080213
Overcurrent, Voltage, Synchronism Check, and Frequency Elements
Instantaneous/Definite-Time Overcurrent Elements
Pickup and Reset Time Curves
and
Neutral-Ground
Instantaneous/
Definite-Time
Overcurrent Elements
Four levels of neutral-ground instantaneous/definite-time overcurrent
elements are available. Two additional levels of neutral-ground
instantaneous overcurrent elements (Levels 5 and 6) are also available.
The different levels are enabled with the E50N enable setting, as shown in
.
NOTE:
The definite-time elements
are not supported in the SEL-351A-1.
To understand the operation of
and
, follow the
explanation given for
,
Instantaneous/Definite-Time Overcurrent Elements on page 3.1
substituting current I
N
(channel
IN
current) for phase currents and
substituting like settings and Relay Word bits.
50BC1 = 1 (logical 1), if I
BC
> pickup setting 50PP1P
= 0 (logical 0), if I
BC
≤
pickup setting 50PP1P
50CA1 = 1 (logical 1), if I
CA
> pickup setting 50PP1P
= 0 (logical 0), if I
CA
≤
pickup setting 50PP1P
Summary of Contents for SEL-351A
Page 10: ...This page intentionally left blank Courtesy of NationalSwitchgear com ...
Page 16: ...This page intentionally left blank Courtesy of NationalSwitchgear com ...
Page 34: ...This page intentionally left blank Courtesy of NationalSwitchgear com ...
Page 126: ...This page intentionally left blank Courtesy of NationalSwitchgear com ...
Page 184: ...This page intentionally left blank Courtesy of NationalSwitchgear com ...
Page 198: ...This page intentionally left blank Courtesy of NationalSwitchgear com ...
Page 228: ...This page intentionally left blank Courtesy of NationalSwitchgear com ...
Page 278: ...This page intentionally left blank Courtesy of NationalSwitchgear com ...
Page 384: ...This page intentionally left blank Courtesy of NationalSwitchgear com ...
Page 410: ...This page intentionally left blank Courtesy of NationalSwitchgear com ...
Page 450: ...This page intentionally left blank Courtesy of NationalSwitchgear com ...
Page 454: ...This page intentionally left blank Courtesy of NationalSwitchgear com ...
Page 472: ...This page intentionally left blank Courtesy of NationalSwitchgear com ...
Page 504: ...This page intentionally left blank Courtesy of NationalSwitchgear com ...
Page 558: ...This page intentionally left blank Courtesy of NationalSwitchgear com ...
Page 562: ...This page intentionally left blank Courtesy of NationalSwitchgear com ...
Page 586: ...This page intentionally left blank Courtesy of NationalSwitchgear com ...
Page 608: ...This page intentionally left blank Courtesy of NationalSwitchgear com ...
Page 666: ...This page intentionally left blank Courtesy of NationalSwitchgear com ...